A significant proportion of blood transfusions given to mothers around the time of birth may be unnecessary, Canadian researchers report in the journal Obstetrics and Gynecology.

Dr. Jeannie L. Callum of Sunnybrook and Women’s Health Sciences Centre, Toronto and colleagues note that although such transfusions are not uncommon, as a general rule they “should be given only when absolutely necessary.”

The team examined data on more than 33,000 obstetrics-related hospital admissions, and found that blood transfusions were given to 216 women. There were 83 vaginal deliveries, 94 cesarean deliveries and 42 operations for pregnancy-related problems.

Overall, 779 units of blood were transfused, which amounted to about 2 units per patient. The most common reason was for bleeding that occurred after delivery.

Based on current hospital transfusion guidelines, about one third of the units were given inappropriately. In 37 cases, transfusions would not have been used, had the guidelines been followed correctly.

Among questionable reasons for use were giving extra blood to patients to relieve anemia-related symptoms and transfusions given to patients who had stable vital signs and adequate lab tests, despite ongoing bleeding.

Overall, the researchers call for education to promote better adherence to guidelines and note that treatment with iron pills or injections “might have prevented transfusion in 11 percent of the women in the (group) who were possibly iron deficient.”

SOURCE: Obstetrics and Gynecology, November 2004.